1. Field of the Invention
This invention relates to plowing and earth ripping devices, and more particularly, to vibrating plows or rippers in which the conventional forward movement of tines or ripper blades through the earth is combined with an oscillating or vibrating movement of the blades or tines to enhance the earth breaking and ripping efficiency of the apparatus.
2. Brief Description of the Prior Art
In my U.S. Pat. No 3,339,641, issued Sept. 5, 1967 and entitled "VIBRATING PLOW", I disclosed a ripper apparatus which functions effectively for breaking up hardpan or, in industrial applications, for breaking and fragmenting old pavement when it is desired to re-surface roadways, parking lots or the like.
Several forms of the apparatus are illustrated and described in my patent, but each basically includes a primary or main frame adapted to be towed behind a towing vehicle, and having a vibrating frame pivotally mounted thereon for pivotation about a horizontal axis as the vibrating frame undergoes an up and down vibrating movement. The vibrating frame, in one form of the vibrating plow there illustrated, has an elongated, tranversely extending tool bar connected across the vibrating frame at the rear end of the machine. A plurality of tines or ripper blades are detachably connected to the tool bar for penetration of the earth during operation of the machine. As the vibrating plow or ripper is pulled forward by the towing vehicle, the ripper blades are pulled through the earth in a horizontal direction, and are concurrently caused to undergo an up and down vibrating movement in which the blades act as vertically impacting chisels. This compound motion effectively fragments or fractures the earth, and has been found highly useful in breaking up hardpan for agricultural purposes, or in fracturing old pavement where pavement removal is desired preparatory to re-surfacing a roadway.
A number of other types of vibrating plows or earth ripping devices which employ an oscillating or vibrating motion imparted to chisel blades or rippers have been developed. Among these, several have been patented and are illustrated in Talbert U.S. Pat. No. 2,935,140; Patton U.S. Pat. No. 3,211,236; Harshberger U.S. Pat. No. 2,792,769; Hubert U.S. Pat. No. 939,132; Talbert U.S. Pat. No. 3,106,968; Lamb U.S. Pat. No. 3,103,250; German Pat. No. 369,256 and published Australian Patent Applicaton No. 5123/26.
Two principal difficulties have been experienced in utilizing the vibrating plow apparatus described in my prior U.S. Pat. No. 3,339,641. One of these difficulties is the propensity of the plow, when used for ripping asphalt and similar surface encrustations of limited frangibility, to fracture the asphalt in large chunks or plates. The large size of the asphalt plates renders the further processing of the asphalt difficult, particularly the loading of the asphalt into trucks for transport to a reclamation facility.
Another difficulty which has characterized the use of my vibrating plow has been the extent to which a forwardly directed horizontal component of force developed during the vibration of the plow is transmitted from the plow apparatus to the towing apparatus. This force tends to periodically impart a shoving or pushing motion to the towing apparatus, thereby imposing certain mechanical stresses on the towing vehicle which are undesirable. Moreover, such forwardly imparted imtermittent or oscillatory motion greatly increases the discomfort of the operator of the towing vehicle, and decreases the uniformity with which the vibrating tines or blades fracture the soil or asphalt through which they are moving.